Re: "Bourbon by definition must be sour in nature"

Interesting question, Roger. It actually made me think of Scotland, where I understand whisky cannot be called Scotch whisky if elements of its processing that have become traditional are not followed. For instance, I believe it would not be proper there to hasten or affect the maturation of Scotch whisky using pieces of wood suspended in barrels. (I haven't studied this but this is what I gather from reading the whisky press over the years). I would think though, if the Canadian rules applied in the U.S., that it shouldn't matter if sweet mash is used for bourbon. Because, I don't think the taste is significantly affected by that but it is more a process control matter, at least as I understand it. Even if the taste was somewhat affected, I don't think that should matter because it is still a method of fermentation and the main tastes still come from the grains and the barrels. You could make an analogy to the still, while continuous stills have become very common and indeed for generations, the pot still can also still be used to make bourbon as indeed B-F and others have shown in recent years. Also, I think sweet mashing was used for a lot of rye production into the 50's and 60's, at least in Maryland and Pennsylvania, so it is not really that long since it was last used commercially.

Re: "Bourbon by definition must be sour in nature"

Chris discussed the sweet mash loss at the last Woodford Bourbon Academy. He explained the loss in this way - The first day of the mash is critical as the yeast takes hold and dominates the mash. In that first day it is possible for airborn bacteria to contaminate the mash. The bacteria does not like an acid environment and that is why sour mashing helps prevent this infection of bacteria. The sweet mash is not protected with the acidic nature of the mash and thus became infected in two fermenters.

The fermenters at Woodford are cyprus but they are steam cleaned before filling so I doubt that there was bacteria in the wood, but I guess it is possible. Chris did not think that was the cause and I see no reason to doubt his conclusion.

Re: "Bourbon by definition must be sour in nature"

Originally Posted by Gillman

I would think as Chuck says few craft distillers use the process, due to their batch approach to distillation. You need a larger scale, continuous method of working to use backset in a methodical way. Backset in the mash, sometimes also used in the fermenter, tends to optimize function of the yeast and minimize the chance of poor or inconsistent fermentations.

We use sour mash for all of our whiskies. Rye, Bourbon, etc.

It's pretty easy to do, actually, so long as you are mashing every day.

As for wooden fermenters, unless you are steaming after every fermentation, those things will be loaded (relative to a modern brewery fermentation, that is) with lactobacillus after a few turns simply because those little buggies ride in with the distiller's malt. Unlike brewing, the mash is never boiled....well, at least not the malt portion of the mash....so the bacteria is never killed.

And I have to respectfully disagree with Mr. Morris. Sour mash will add excess Free Amino Nitrogen and well as autolysed yeast cells to the fermentation...two things that lactobacillus and other bacteria love. In my opinion and experience, a sour mashed fermentation is much more likely to spoil than a sweet mash, although I can only speak to my processes, and not to Mr. Morris'. A lower pH helps to stabilize any fermentation, but lovers of sour beer will tell you that lactobacillus and Brettanomyces function just fine south of a 4.0 pH.

You have to have one hell of an infection to affect a 3 or 4 day fermentation more than just a little. It's when all the sugars are gone that infections do their thing. The choice for the distiller becomes: do I let the fermentation sit for a few more hours/days to allow the "infection" to take hold? Or do I drop it into the still immediately, allowing for the majority of the fermented flavors to have come from the culture yeast(s)?

At our shop, we let the lactobacillus do its work after the yeast mops up any and all sugars, and have ceased fermentation. This leads to more complex esters down the road in the barrels.

Re: "Bourbon by definition must be sour in nature"

We use sour mash on our bourbon, corn and rye. not just because it is the traditional way to do things, We use it because it works. I agree with Chuck though. I dbout very many small distilleries use it, they have a hard time even boiling corn. Plus Bill Owens probably tells them not to.

Re: "Bourbon by definition must be sour in nature"

There is one more when they are making rye, I consulted with them. Cascape Peak in Oregon. Bill really thinks he is helping, but I think that alot of people that have no idea about distilling look to him for instruction. And in my opinion, he does not know enough to be advising anyone. For instance, I have spoken to him about making traditional bourbon and he is just completly uninterested. He has done a lot to bring people together, but I think he promotes shortcuts too much.

Re: "Bourbon by definition must be sour in nature"

Todd, it's true that lactic acid bacteria can work with yeasts to produce the sour tastes in beverage beer you mentioned, but I would think in distilling, since the mash or wash is not held for very long, those bacteria (and brett yeasts too) don't have time to do much damage.